1. Field of the Invention
This invention relates to magazines for holding captive and feeding electronic or electrical component packages or modules, more particularly a packaged integrated circuit assembly known as a dual-in-line-package or DIP. A DIP has two sets of spaced leads arranged in parallel rows disposed on a slight angle at the sides of a generally rectangular insulating body encapsulating the circuitry and chip of the integrated circuit.
Integrated circuit packages are required to be supported in carriers or magazines in order to protect them against damage during handling and testing, especially when handling, such as is involved in connection with routine temperature and moisture cycling procedures and the mechanized loading, feeding, sorting, marking, classification and testing, when performed by automatic mechanical handling equipment. In particular, a high degree of care is required to prevent subjecting the leads of the integrated circuit to pressures and stresses as might cause cracking of the delicate dielectric body of the integrated circuit module. It is highly desirable that manual handling and manual operations be minimized in this field both from the quality control and cost standpoint.
2. Prior Art
Elongated magazines comprising continuously-extruded plastic tubes of various length and cross-sectional configurations, generally matching the configuration of the inserted packages including the angle of the protruding rows of terminals, have been utilized for protective purposes. These are adapted to interface into various automatic machinery for performing the above feeding, sorting, marking, etc. functions. These magazines shown in U.S. Pat. Nos. 3,655,041 and 4,327,832 generally have been of an open-ended construction with the DIP's held in end-to-end relationship along the magazine or rail length.
Discrete pins or end stop plugs insertible into end apertures have been employed to prevent the DIP's from sliding out either end of the magazine when it is tilted or vibrated. Such a discrete pin or plug is seen in U.S. Pat. Nos. 4,077,557 and 4,295,258. In the latter patent and U.S. Pat. No. 4,207,665 a separate means is provided to insert or pull pins from vertical apertures contained in the magazine or shipping rail. Most pins, plugs or end wedges, however, are pulled out by a hand held claw type puller, by pliers or by an operator finger gripping or prying with a fingernail. Thumb or hand pressure is normally used to insert the pins. Pins can become lost or dropped into high tolerance machinery and their manipulation either by hand or by a puller involve time-consuming effort by an operator, lessening the production capabilities of the production or test line. It has been estimated that as much as thirty percent (30%) of operator time is spent installing and removing pins from the ends of semiconductor package magazines. Manual handling of the opening of the ends of the rail also can cause inadvertant emptying of one, or usually many more, DIPs from the magazine, with attendant damage to the DIPs from a fall to a floor or table. This problem is compounded when one wishes to feed or mount the magazine in an inclined guide on automatic machinery, wherein the DIPs are fed by gravity into a processing station such as for test or marking as shown in U.S. Pat. No. 3,701,021. A further type of closure is seen in U.S. Pat. No. 3,435,949 in which removal closures block the ends of the magazine.